Admission Screening Testing of Patients and Staff N95 Masks are Cost-Effective in Reducing COVID-19 Hospital Acquired Infections

Background: COVID-19 outbreaks in acute care settings can have severe consequences for patients due to their underlying vulnerabilities, and can be costly due to additional patient bed days and the need to replace isolating staff. This study assessed the cost-effectiveness of clinical staff N95 masks and admission screening testing of patients to reduce COVID-19 hospital-acquired infections. Methods: An agent-based model was calibrated to data on 178 outbreaks in acute care settings in Victoria, Australia between October 2021 and July 2023. Outbreaks were simulated under different combinations of staff masking (surgical, N95) and patient admission screening testing (none, RAT, PCR). For each scenario, average diagnoses, COVID-19 deaths, quality-adjusted life years (QALYs) from discharged patients, and costs (masks, testing, patient COVID-19 bed days, staff replacement costs while isolating) from acute COVID-19 were estimated over a 12-month period. Findings: Compared to no admission screening testing and staff surgical masks, all scenarios were cost saving with health gains. Staff N95s + RAT admission screening of patients was the cheapest, saving A$78.4M [95%UI 44.4M-135.3M] and preventing 1,543 [1,070-2,146] deaths state-wide per annum. Both interventions were individually beneficial: staff N95s in isolation saved A$54.7M and 854 deaths state-wide per annum, while RAT admission screening of patients in isolation saved A$57.6M and 1,176 deaths state-wide per annum. Interpretation: In acute care settings, staff N95 mask use and admission screening testing of patients can reduce hospital-acquired COVID-19 infections, COVID-19 deaths, and are cost-saving because of reduced patient bed days and staff replacement needs. Funding: Victorian Department of Health. SM and NS are the recipients of National Health and Medical Research Council fellowships. Declaration of Interest: The authors declare that there are no competing interests. Ethical Approval: Approval from a Human Research Ethics Committee was not required as only aggregated values were used to inform model input parameters, which were routinely collected by the Victorian Department of Health as part of its public health function pursuant to the Public Health and Wellbeing Act 2008 (Vic) and the Health Records Act 2001 (Vic).